Switch control and indication system



2 1950 P. M. BRANNEN SWITCH CONTROL AND INDICATION SYSTEM Filed Jan. 30, 1947 INVENTOR. Paul Bpannazz.

Hair-14 zealyzey Patented Jan. 24, 1950 UNITED- STATES PATENT OFF I CE SWITCH CONTROL AND INDICATION SYSTEM Application January 30, 1947, SerialN'o. 72 51231 3'Claimsr (Cl. 246-219) My invention relates to'railway'switch controlling and indicating apparatus and particularly to apparatus for controlling and indicating an -electricallyoperated switch:

Where a considerable distance separates the control point and the switch operated' therefrom, it is desirable to use the least number of conductors' between the two locations.

An object of this invention is to provide an improved switch control and indicating system ofthe type described inwhich only two conductors are used forthe purposes of controlling the switch and indicating its position, and in which" the two conductors at times provide achannel ior'co'ntrolling the position of an electrically operated switch, in addition to oai'ryin'g the energy for op eration of the switch motor; and at other times provide a channel for indicating the position of the switch.

Another object of" the-invention is toprov-i'de' improved switch control and indication means which may be employed in situations in which the energy for operatingthe switch i's'pro'vided by a hand operated generatora-t' theofiic'e;

In practicing my invention; I provide twoconductors extending from the control point, or price; to the switch location, which arenormallyrconnected at the ofii'ce to a polarized indication-ro lay, and at the-switch location, to a low voltage source of energy'through circuit COfltlO11illg'-a;p-- paratus for-providing an indication'of the position of theswltch.

When. the hand generaton'at theofiiceis operated and its voltage reaches a predetermined value; it energizes a transfcrrelay at the oflice,

causing the two. conductors to be disconnected fronrthe indication relay and tobeconnectedwith the hand generator terminals through a pole changing device. Accordingly, a relatively high voltage. of one polarity or the other is placed" across the conductors, causing'a polar neutral switch control relay at theswitch location which is connectedacross the conductorsto become en' ergized. The neutral contacts of this'relay there'- upon pick up to connect the two c'onductors to the. motor of the electrioswitch; which then becomes energized in a direction determinedy the polar-contacts of the switch controlrelay and" operates the. switch to one position-or the-"other; depending on the polarity ofthe supplied energy. In addition, when the neutral contacts of the switch control relay are picked up they interrupt the connection between the line wires and the source of energy for operating the indication re' lay at'th'e' OffiCB.

its -control relay, and also-i'n-the event of an overload;

Other objects of the invention and features of novelty will be apparent from the following de Soription' taken in connection with the accompanying drawing I shall d'escrihe a'preferred form of switch control andindication' system embodying my invention; andshall then point out the novel features thereof in claims.

Referring to thc accompanying drawing, which is-a-view of a preferred embodiment of my invent'ion, there'is shown at" the office a hand operated direct current generator G, which may be operated to supplyenergy ofa relatively high voltage to-conductors 9 and lfl bya circuit includingthe pole changin contacts H and I2 of a lever L and front contacts I5 and I6 of'transfer relay W'CR. Back contacts [5 and I6 of relay WCR normally connect the-Winding of polarized indication relay W-PR, which will operate on a relatively low Voltage, to-conductors 9 and Ill. The winding of relay WCR isconnected across the generator G- anditsoperating characteristics are such that it will pickuponl'y after the voltage of the energy supplied by the generator has rea'che'd'apredetermined value. Contacts Hand I8 of relay WPR are illustrated as controlling indication lamps 48: and 50'', supplied with energy from asuitable source, not shown, Whose positive and negative terminals are denoted as BX and CX, respectively, butthese contacts or other contactson the relay: may be employed to control other types of indication means or may .be employed for: any other. appropriate purpose.

At the field location there is shown a track switch W; which is moved between a normal and a reverse position by means of'amotor'M which is designed to operate on direct current; The motor drivesthe switch through: suitable mechanism, not shown.

Associated-with the motor are a switch control relay'wRga quick acting relay WCPR, and an overload relay OR; The winding of relay WR, which=is connected across'conductors 9 and i0, hasahigh resistance, so that a relatively high voltage must be supplied in order for it to operate, and is governed by a back contact 25 of relay OR.

The equipment is shown in the condition which it assumes when the switch W and the control lever L are in their normal positions, and the hand generator is not being operated.

As there is no energy supplied to the Winding of transfer relay WCR, its back contacts l5 and I6 connect the winding of indication relay WPR to the conductors 9 and I0. Relay WPR is a polarized relay having a low resistance winding, and will operate on energy of relatively low voltage. At this time relay WPR is energized by a suitable low voltage source of direct current at the field station, such as a battery, not shown, whose positive and negative terminals are denoted as B and C, respectively. This circuit is traced from positive terminal B, through blocking rectifier K, over normal polar contact 2| of relay WR, normal contact 22 of the switch indication circuit controller, back contact 23 of relay WPCR, back contact 24 of relay WR, over conductor l0, back contact l5 of relay WCR, through winding of relay WPR from left to right, over back contact N5 of relay WCR, conductor 9, back contact 25 of relay WR, normal contact 29 of the switch indication circuit controller, over normal polar contact 30 of relay WR, and through the resistor R. to negative terminal C. The winding of relay WPCR has a high resistance, and the energy supplied by the indication source is insufficient to cause the relay to pick up its contacts. Accordingly, relay WPR is energized with energy of normal polarity and its neutral contact ll is picked up while its polar contact l8 occupies its normal position, and these contacts establish a circuit to light normal indication lamp 49 to show that the switch occupies its normal position.

Contacts 22 and 29 of the switch indication circuit controller are operated by the movement of the switch so that when the switch is in its normal position the normal contacts are closed and when the switch is in its reverse position the reverse contacts are closed, while both contacts are open when the switch is in transit. Resistor R is a current limiting resistor which limits the flow of high voltage energy through the source of indication energy should the operator operate the hand generator without operating lever L.

If the operator desires to move the switch W to its reverse position, he may do so by moving the control lever L to its reverse position and operating the generator. When the generator output voltage becomes sufiicient, relay WCR picks up and disconnects wires 9 and ID from the winding of relay WPR and connects these wires to the generator through contacts II and I2 of the lever L. Accordingly, relay WPR is released, and contact I! interrupts the supply of energy to normal indication lamp 49. Positive high voltage is supplied over reverse lever contact front contact |5 of relay WCR, through conductor I0, over back contact 24 of relay WR, back contact 23 of relay WPCR, normal circuit controller contact 22, and over normal polar contact 2| of relay WR, but is prevented from causing the flow of current to terminal B by the rectifier K which is poled to permit current to flow from terminal B to polar contact 2 l, but prevents the flow of current in the opposite direction.

The high voltage present across the terminals of relay WPCR causes this relay to pick up quickly and its back contact 23 in the circuit previously traced disconnects the source of energy for the switch indication from the control conductors 9 and I0, and as a result prevents overloading of the indication circuit by the high voltage operating energy until such time as relay WR picks up and further isolates the indication circuit from the line circuit, while the relay WR now receives sufiicient energy fom the control conductors 9 and Hi to operate its contacts, and the polarity of the energy supplied is such that its polar contacts move to their reverse position, and its neutral contacts pick up, interrupting the connection between the conductors 9 and ID and that portion of the circuit including the source of indication energy and the relay WPCR. The energy supplied to relay WPCR by the source of indication energy is insufficient to retain relay WPCR in its picked-up position, and accordingly relay WPCR releases and its back contact 23 closes. However, the connection of the low voltage source to conductors 9 and i0 is now inter rupted by the neutral contacts 24 and 25 of relay WR, and also by the reversal of the polar contacts 2| and 30 of relay WR.

When the contacts 24 and 25 of relay WR pick up, they establish a circuit to energize the switch motor operating circuit so as to operate the switch to its reverse position. This circuit is traced from the positive brush 5 of the generator G, over pole changing contact front contact l5 of relay WCR, through conductor l0, front contact 24 of relay WR, reverse polar contact 32 of relay WR, switch operated contacts 34 and 35, field 38 of motor M, reverse polar contact 40 of relay WR, armature 4| of motor M, thermal resistance 42 and the pick-up winding 43 of overload relay OR in multiple, front contact 25 of relay WR, through conductor 9, over front contact l6 of relay WCR, and over pole changer ccntact |2 to the negative brush 6 of the generator G. The motor armature and its field Winding are energized in series and the various parts are arranged so that the motor operates to move the switch W to its reverse position.

The contact 35 is operated in accordance with the movement of the switch and is arranged so that it engages contact 34 in all positions of the switch except the reverse position, and so that it engages a contact 36 in all positions of the switch except the normal position. Accordingly, when the switch completes its movement to its reverse position, contact 35 is moved out of engagement with contact 34 to interrupt the circuit traced above for supplying energy to the motor M and the motor ceases to operate. Interruption of the motor circuit by contact 35 removes the load from the generator G, and the resulting reduction in the efiort required to operate the generator indicates to the operator that the switch has completed its movement, and that further operation of the generator is unnecessary. When the generator speed decreases sufiiciently, the output voltage falls below that required to retain relays WCR and WR picked up, and these relays then release. Assuming that the switch W has completed its movement to the reverse position and contacts 22 and 29 have been operated to their revers position, a circuit is now established to energize relay WPR. This circuit may be traced from positive terminal B, through rectifier K, over reverse polar contact 2| of relay WR, reverse contact 29, back contact 25 of relay WR, through conductor 9, over back contact I6 of relay WCR, winding of relay WPR from ri ht to left, over back contact l5 of relay WCR, conductor Ill, back contact 24 of relay WR, back contact 23 of relay WPCR, reverse contact 22,

reverse polar contact 30 of relay WR, and through'resi'stor Rto terminal C. Accordingly; relay WPR is energized'w-ith *energy' oi reverse polarity and itspolar contacts move to their reverse position and its neutral contacts pick up; Front contact I! and reverse polar contact 18 of relay WPR. then cooperate to control reverse indication lamp 5i! tosh'ow that the switch is in its revers position.

When the switch is in its'reverse position, the operatormay move the switch to its normal posi tioh by moving the control lever- L to its normal position and operating the'generator. When the generator output voltage becomes sufficient, relay WCR. picks up and connects conductors Sand in to th'ebrushes Sandi; of the generator through contacts I l and l2 'o f the lever L. Relay WPRis released and positive high voltage energy flows through conductor 9 ,'ov'er'ba'ck contact 25 ofrelay WR; reverse contact 29, over reverse polar con tact 2i or-relay WR, but is prevented from flow ing to terminal Bhy r'ectifierK.

Relay WPCR-picks up because ofthe high volt age across its terminals, and its -back contact-23 disconnects the source or indication energy "from the line conductorsir'om which relay WR, now receives suflicient energy to o'perate its contacts an the polarity of the hi h voltage energ is such -that it"s p'ol'ar contacts inove to their nor mal position. When the neutral contacts-of relay WR -pickup,'the si'ip'pl yo'f high voltage energy to il'ay WPCR is interruptemand 'reray'WPcR releases. However, as previously explained, the closing of back Contact 23 of relay WPCR does not connect the source of indication energy to conductors 9 arid since the circuit is further interrupted by the picking :up of c'ontac'ts24 and 'of relay WR.

Also, when contacts 24 and 25 of relay WR pick up, a circuit is established'to supply high volt"- age energy to the motor M, so as to operate the switch from its reverse to its normal position. This circuit is traced from the positive brush 5 of generator G, over pole changing contact ll, front contact 16 of relay WCR, conductor '9, front contact "25 of relay WR, through thermal resistor 42 and pick-up winding 43 of overload relay OR in multiple, motor armature 4 I, over normal polar contacttfi of relay WR, contacts and 36, through the field winding 38, normal polar contact 32 of relay WR, front contact 24 of relay WR, through conductor ii), over'front con-tact I5 of relay WCR, and pole changing-contact d2 of lever L to the negative brush 6 of generator G. The

motor armature and its field winding are energ'ized'in series and the parts are arranged so that the motor operates to move the'switch W to its normal position. When the switch completes its movement to its normal position, contact 35 is moved out or engagement with'contact 36 and interrupts the circuit traced'above for supplying energy to the motor M and the motor ceases to operate. The removalof the load from the generator indicates to the operator th'atthe switch has completed its movement and further operation of the generator is unnecessary. When the generator output voltage drops below theyalu'e necessaryto retain relays WCR and WR picked up, these relays release, and again establish a circuit for energizing relay WPR. Assuming that the switch completed its movement to its normal position, restoringfcontacts 22 and 29 to their normal position, energy'of normal polarity is suppliedtorelay by the circuit'previously traced for the normal condition of the apparatus.

Accordingly, the polar contacts of relay WPR. move to their normalrposition, arid the neutral contacts pick up. Front contact I! and normal polar contact I8 of relay WPR then establish the circuit of the normal indication lamp 49.

The thermal resistance 42, which is included in series with the"'circuit for supplying energy to the motor, has a positive thermal coefficient of resistance, that is, the 'resistance oi the unit increases as the temperatureof the material-of which it is constructed increases.

"The terminals of the pick-up winding 53 of the overload r'el'ay OR are connected acrossthe therma; resistance, .while means are provideii to shunt the high resistance holding winding [9 when thecontacts of this relay are released and to energize the homing Winding l9 from the Conductors Q' al'ld ii! the overloa'd'rela'y c011 t'acts are picked up.

The relay GR is equipped witheonta'cts er the inake-loefore breaktype, and as shown, the righthand terminal of the holding winding ts is connected to movable contact 45, which, when released, engages stationary contact "46 which is connected to the left-hand terminal of the wind-' i-n'g Iii. Accordingly, as long as the contacts of relay OR, are released, the holding windin 1 9 of relay GR is short circuited by the circuit controlled by contacts 45 and 46. As the winding i9 is short circuit-ed when the relay contacts are released, the relay contacts are rendered slow in pickii'i'g up and the "ov'erliiiad relay will not respond to momentary surges in the current in the motor circuit, A

I As previously explained, "the 'energysuppliecl to the motor M is supplied over the circuit which in"- clu'des in series therewith the resistor 42 and the overload relay pick-up :winding 43 in multiple. On the supplyof energy to the motor M a portion or the"ener' 'gy supplied to the motor is supplied through the pick=upwinding '43 of relay OR. As a result of the supply of energy to'th'e motor M, the resistance 42 becomes heated and its resistance increases "so that there is a corresponding increase in the value of the current supplied through the pick-up winding 43 of relay "OR.

The various parts of the apparatus are arranged arid proportioned so that under normal conditions 'mostof the energy supplied to the motor is supplied through the resistor 42, while the current supplied through the winding 43 oi relay OR is of too small value tofpi'ck up the relay contacts. Accordingly, the contacts of the relay OR remain'released and cohtact Zil maintains 'thecirc'uit for connecting the winding of "relay WR across the conductors i! "and it so "that thefheutral contacts 24 and 25 of relay WR remain picked up and 'in'ai'ntain the supply of energy to the motor until "the switch completes its movement,andcausescontact 35to interrupt the (fircuitfdf the switch 'inotor.

The -yari ou's parts of the equipment are also arr nged and pr opditioned so that if the imoto'r M draws current or unusuanyhigh value for an abnormally long period, as occurs when movemerit of the "switchis obstructed, the resistance 42 will become heatedto a temperature such that its resistance increases to a degree efiective to cause the current 'suppliedth'rough the winding 43 b f 're'lay OR to be great enough to pick up the relay'contacts M On movm'ent of "the contacts of relay OR towards their picked-u position, "contact in en, gages contact "'45 to thereby establish a circuit to energize the holding winding is mini "the conductors 9 and I0, while contact 41 moves contact 45 out of engagement with the stationary contact 46 to interrupt the circuit short circuiting the winding Hi.

If the switch is being moved to its normal position at the time the overload condition occurs, energy flows through the pick-up winding 43 of relay OR from right to left, and if the switch is being moved to its reverse position at the time the overload condition occurs, energy flows through the winding 43 from left to right. The right-hand terminal of the holding winding [9 of relay OR is connected to conductor 9 by a circuit including contacts 45 and 41, and the left-hand terminal of winding I9 is connected to conductor ill by a circuit having in series therewith a resistor 44, so that when high-voltage energy of normal polarity is supplied to conductors 9 and Hi to operate the switch to its normal position and an overload condition causes relay OR to pick up, energy will flow through the holding winding IQ of relay OR from right to left, whil when high-voltage energy is supplied to conductors 9 and ID to operate the switch to its reverse position and an overload condition causes relay OR to pick up, energy will flow through winding [9 from left to right.

Accordingly, the energy supplied to the holding winding 19 of relay OR flows through this winding in the same direction as the energy which is supplied to the pickup winding of the relay. As a result, the energy supplied to the pick-up and holding windings of this relay cause flux of the same polarity to be developed in the relay core so that on picking up of the relay contacts, and resultant supply of energy to the relay holding winding, the relay contacts are maintained picked up.

In addition, on picking up of the contacts of relay OR, its contact 20 interrupts the circuit of the winding of relay WR so that neutral contacts 24 and 25 of this relay release and interrupt the supply of energy to the motor and the pick-up winding of relay OR. Back contacts 24 and 25 of relay WR connect the source of indication energy to the line, but the high voltage causes relay WPCR to pick up and isolate this portion of the circuit, as previously described. Relay OR remains picked up, however, by energy supplied to the holding winding l9 as long as the generator at the office is operated.

The resistor 44 which is in series with the holding winding serves to limit the flow of lowvoltage indication energy through the holding winding [9, and serves to limit the current flow at the moment the overload relay contacts pick up, since when contact 4! engages contact 45, and before contact 45 moves out of engagement with contact 46, a connection is established between conductors 9 and I0. This circuit is interrupted as soon as contact 45 is moved away from contact 46, but the resistance 44 prevents excessive current flow in this circuit during the momentary period in which the circuit is established.

When an overload condition occurs, and relay OR picks up, thereby causing relay WR to release, the load of the switch motor is removed from the generator G, and the operator is made aware of an abnormal condition by the lessening of the effort required to operate the generator. He may then cease to operate the generaator, and if the switch has become stalled at some point in transit, no indication will be received, since contacts 22 and 29 will be open.

He may then place the control lever L in the other position, and again operate the generator to move the switch to its other position. Since no energy was supplied to relay OR when the operator ceased the operation of the generator, relay OR will release and interrupt the previously traced circuit for energizing the holding winding l9 from conductors 9 and Ill.

Back contact 29 of relay OR establishes the circuit for energizing relay WR, so that when high-voltage energy is again supplied over conductors 9 and i0, relay WR will pick up, and if the polarity of the energy differs from that previously supplied, the polar contacts of relay WR will move to their corresponding positions and will establish circuits to cause the motor to move the switch away from the obstruction.

From the foregoing it will be seen that this system is arranged so that on picking up of the contacts of overload relay OR a circuit is estab-' lished to energize the holding winding of the relay from the control wires to thereby maintain the relay contacts picked up, while a contact of the overload relay interrupts the circuit of the switch control relay WR to cause it to interrupt the circuit of the switch motor.

It will also be seen from the foregoing that this system provides means for the control and indication of an electric track switch which has as its source of operating energy a hand operated generator, using only two conductors between the control office and the location of the switch.

Although I have herein shown and described only one form of a switch control and indication system embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

l. A system for the remote control and indication ol a railway track switch over a pair of conductors extending from a control oflice to the switch location comprising a hand operated direct current generator, a transfer relay having its winding connected across the terminals of said generator, pole changer contacts for selecting the direction of movement of the track switch, and a low resistance indication relay, all located at said office; a high resistance polar neutral control relay having its winding con-- nected across said conductors, a switch machine having a motor for operating the track switch and contacts for indicating its position, and a low voltage source of energy, all at the switch location, the voltage of said source being insufficient to operate said control relay; a circuit over which said indication relay is normally energized by current from said low voltage source to indicate the position of the switch at said office including back contacts of said transfer relay, said conductors, back neutral and polar contacts of said control relay, and said switch position indicating contacts, normal and reverse operating circuits for said switch motor supplied with current from said generator in response to its hand operation including said pole chan er contacts, front contacts of said transfer relay, said condoctors and front neutral and polar contacts of said control relay, and means at the switch location for opening said normal or reverse oper' ating circuit to indicate at the office the termination of the movement of the track switch by the resulting decrease in the effort required to operate said generator.

2. A system for the remote control and indication of a railway track switch over a pair of conductors extending from a control office to the switch location comprising a hand operated direct current generator, a transfer relay having its winding connected across the terminals of said generator, pole changer contacts for selecting the direction of movement of the track switch, and a low resistance indication relay, all located at said oflice; a high resistance polar neutral control relay having its winding connected across said conductors, a switch machine having a motor for operating the track switch and contacts for indicating its position, and a low voltage source of energy, all at the switch location, the voltage of said source being insuflicient to operate said control relay; a circuit over which said indication relay is normally energized by current from said low voltage source to indicate the position of the switch at said ofiice including back contacts of said transfer relay, said conductors, back neutral and polar contacts of said control relay, and said switch position indicating contacts, and normal and reverse operating circuits for said switch motor supplied with current from said generator in response to its hand operation including said pole changer contacts, front contacts of said transfer relay, said conductors, and front neutral and polar contacts of said control relay.

3. A system for the remote control and indication of a railway track switch over a pair of conductors extending from a control oflice to the switch location comprising a hand operated direct current generator, a transfer relay having its winding connected across the terminals of said generator, pole changer contacts for select- 10 ing the direction of movement of the track switch, and a low resistance indication relay, all located at said office; a high resistance polar neutral control relay having its winding connected directly across said conductors, a quick acting relay having its winding connected across said conductors over back contacts of said control relay, a switch machine having a motor for operating the track switch and contacts for indicating its position, and a source of indication current the voltage of which is not suflicient to operate said control relay or said quick acting relay, all at the switch location; a circuit over which said indication relay is normally energized by current from said source to indicate the position of the switch at said office including back contacts of said transfer relay, said conductors, back neutral and polar contacts of said control relay, said switch position indicating contacts, and a back contact of said quick acting relay, and normal and reverse operating circuits for said switch motor supplied with current from said generator in response to its hand operation including said pole changer contacts, front contacts of said transfer relay, said conductors, and front neutral and polar contacts of said control relay.

PAUL M. BRANNEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,801,974 Pelikan Apr. 21, 1931 2,097,202 Spray Oct. 26, 1937 2,156,691 Hines May 2, 1939 2,176,611 Pelikan Oct. 17, 1939 

